Tropes A to B (Adaptation-Induced Plot Hole, Arc Villain, Berserk Button, Beware the Silly One, Big Brother Instinct, Bowdlerise, Break the Cutie) | Tropes C to D (Call-Back, Chekhov's Gun, Cliffhanger, Combat Pragmatist, Crouching Moron, Hidden Badass, Curb-Stomp Battle, Dark and Troubled Past, Deconstructed Character Archetype) | Tropes E to F (Early Installment Weirdness, Famous Last Words, Foreshadowing) | Tropes G to J (Heart is an Awesome Power, Hypocrite) | Tropes K to M (Laser-Guided Karma, Logical Weakness, Mass "Oh, Crap!", Moral Myopia, Muscles Are Meaningless) | Tropes N to P (Nice Job Fixing It, Villain, Oh, Crap!, O.O.C. Is Serious Business) | Tropes Q to S (The Reveal, Shout-Out, Spanner in the Works, Superpower Lottery) | Tropes T to Z (Wham Episode, Wham Line)
Just about everybody in One Piece, but considering it's about pirates it's to be expected that they have to be a Combat Pragmatist.
Luffy: There's no such thing as fairness in a pirate fight.
- Most notable on the heroic side is Usopp. He is no more powerful than an average human and is constantly up against people with superhuman strength, martial arts training, or superpowers. As a result, he developed a fighting style revolving around playing dead, distracting his enemy with horrible phrases or noises, smoke screens, oil slicks, etc.
- The first opponent he defeated by playing dead, hiding, dousing him in high proof alcohol, setting him on fire, and pounding him with a hammer until he stopped moving. It was Played for Laughs.
- He defeated another opponent (Perona) by discovering her fear of cockroaches and attacking her purely at the psychological level. He renders her unconscious, foaming at the mouth, using supplies he scrounged up, and never having to deal any physical damage.
- Usopp and his doctor friend Chopper (who is also a Combat Pragmatist himself), when up against two opponents, defeat one of them by creating a smokescreen with Usopp imitating the voice of one of them to provoke the other into whacking her with an extremely heavy bat. Chopper then defeats the other by taking advantage of the former's tunnel network and the latter's explosive baseballs to detonate the entire area.
- In a particularly hilarious case, Usopp discovers his foe is traumatized by a particular image. What does Usopp do? He creates that image, then crashes it through a window she happens to be standing next to, scaring her enough to faint her. No foaming at the mouth this time though.
- Chopper gets a few moments for himself too. One of them is when he goes up against someone who prefers to fight around a swamp full of quicksand-like mud and never has to fear it because he wears rocket boots that lets him fly over the stuff. Chopper ends him with relative ease by dodging one of his swooping attacks and taking off one of the boots, causing the man to lose control and send him zooming headfirst into his own swamp.
- For the bad guys, the early villain Don Krieg is the absolute king of this trope. Nothing is beneath him when it comes to claiming victory. One of his standard strategies is raising a marine flag to get in close on other marines, or pretending to surrender just to fire when his opponents put their guard down. He is seen accepting food at a restaurant. Promising he will not do anything after getting his strength back. When this occurs, he figures the restaurant will be a perfect disguise, as nobody will expect an attack from it, and decides to take it for himself. When it comes to actual fighting, he relies on an insane amount of weapons: an extremely tough armour with hidden guns all over it, diamond-embedded gauntlets that lets him shatter just about anything, shuriken launchers in his shoulderplates, lots of bombs, needle machine guns, again in his shoulderplates, poison bombs, a spiked cape, a wrist-mounted flamethrower, an iron net he can fire to pull opponents into the sea, and last but not least, his main weapon: a one-ton spear that explodes whenever he hits something with it, and every time he strikes with it, it never breaks. The fact that even that guy came back absolutely wrecked (an understatement) from the Grand Line really says something truly bad.
- Two other villainous examples are Diamante and Pica of the Donquixote Pirates; both border on Dirty Coward levels. When fighting Rebecca in the Corrida Colosseum, Diamante steps on her foot to block her and prevent her from moving, before attacking her. Later, when fighting Kyros, not only does he focus almost exclusively on the now-defenseless Rebecca, but he also shoots Kyros's only leg, to prevent him from dodging his Deadly Rain of Spikes of Doom. In the later stages of his fight with Zoro, Pica deliberately avoids him to go and try to finish off the other fighters, who were already heavily weakened; much to Zoro's anger.
- Luffy himself bites, hits people in the crotch, takes human shields, and has hit more women than Ike Turner. Though he does have some rules, such as not ganging up on his opponents, and hitting them In the Back. And when trying to rescue Robin during the Enies Lobby arc, he ends up having to fight Rob Lucci. Throughout the whole ordeal, he's constantly trying to abandon the fight and go after Robin, since she's more important than a fight with the "pigeon guy". He only begins to take the fight seriously once he helps Franky get past, to make sure he defeats Lucci so that he doesn't go after the rest of his crew.
- Sanji is mostly honorable (the only time he kicked a man in the crotch was Filler and he has strict rules on not hurting women or using his hands in a fight), but otherwise he is extremely tactical and will exploit any weakness his opponents have e.g in Arlong Park when Kuroobi was wrecking him underwater, Sanji breathed air through Kuroobi’s gills and forced him onto land where he could turn the tables. An even better example is when Sanji boarded the sea train full of World Government agents, Sanji could’ve fought all the agents as well as Captain T-Bone or instead he could climb over the roof, unhook the carriage, and let the stormy ocean do the rest.
- Sanji, later on, also manages to sink two Marine battleships by himself by locating a control panel for a machine that can alter the nearby ocean currents and adjusts them such that the water sends the battleships hurtling toward each other.
- Zoro has more than a few moments of these, while he's far more honor bound than Luffy or Sanji and will only cut someone in the back if it's emergency, he'll still play dirty or take any advantage he can get. If he's up againist an opponent who's got Nigh-Invulnerability and there's a Kryptonite Factor (Sea Stone) nearby, Zoro will do his best to grab it, or if he's handcuffed to another person and can't use his sword properly, he'll make the person hold his katana while he swings them around. Also as Filler shows, if he gets caught without his swords, Zoro will make use of three mops instead. At one point in Wano, Zoro uses the scythe he was just stabbed with along with his other swords as part of his Fantastic Fighting Style. At another point, Zoro is sentenced to seppuku and given a tantou blade to kill himself with, then turns the tables and defeats everyone in the room using the tantou.
- Nami much like the rest of her crew will take any advantage she can get and her fighting style revolves using her Weather Manipulation (Clima Tact) to turn the elements against her foes or create mirages to make up for her lack of superhuman prowess. Even without her Clima Tact, Nami will trick, seduce, and outwit foes; one time in Filler she distracts Eric the Whirlwind, a Devil Fruit user, and kicks him into the ocean, effectively killing him. In Whole Cake Island, she manages to lure Big Mom's homie Zeus with the Clima Tact, then weaponizes him against Big Mom to spectacular effect.
- Robin is brutally pragmatic with her Devil Fruit usage; whenever she's decisively fighting to kill/cripple an enemy, she just uses her Hana-Hana No Mi to sprout arms on the opponent and break their necks or spines. However, because Rule of Drama exists and dictates this would be too easy, many of her designated opponents tend to be immune to spinal column damage.
- Blackbeard has no qualms about doing anything to win. Being an opportunist, he sometimes waits until his target is already weakened to finish them off. He also has no problem calling his crew to help him gun down an enemy who is beyond him, like Whitebeard.
- Jinbe is a remarkably practical Fishman, even back in his introduction in Impel Down he helped his allies escape the prison by summoning a group of whale sharks. In Whole Cake Island he frees Luffy and Nami from a book cage by burning the pages and later when Katakuri traps Luffy with his Mochi Devil Fruit powers, Jinbe frees his future captain by using his Making a Splash power in some nearby tea. When fighting Big Mom, Jinbe takes every advantage he can get including using Megaton Punch to knock her into the ocean where she’ll sink and using water on her fire shooting Soul Jar Prometheus. In Wano Jinbe uses Big Mom’s weight against her, judo throwing her while the aforementioned Robin uses her power to make sure Big Mom keeps rolling out of the room.
- Pedro averts Transformation Is a Free Action by detonating a bunch of dynamite in an attempt to take out both his enemy and said enemy's reinforcements.
- Vinsmoke Judge is also adamant on using every means at his disposal to make his fight with Sanji end decisively, rules be damned. Whether it's using his soldiers as meat shields to make Sanji hesitate, kicking Sanji while he's down, or using advanced weaponry against an unarmed opponent (Although granted, Sanji refused to use the sword Judge offered him before the fight). Also Judge makes it clear later he’s helpless without the Raid Suit, meaning he was cheating against his son from the start.
- Charlotte Katakuri is extremely tactical, killing any potential threats before they happen and even refused to let Luffy go Gear Fourth when he first tried and stated he wouldn't let Luffy get any advantage. But ultimately Katakuri subverts when outside forces interfere with the fight and weaken Luffy, Katakuri injures himself as to put him in same state as Luffy and declares they will fight fairly from there on.
- The Red Scabbards (Kin'emon, Denjiro, Kikunojo, Raizo, Ashura Doji, Inuarashi, Nekomamushi and Kawamatsu) honourable Samurai they may be still won’t play fair in a fight against a vastly superior opponent as seen in their fight with Emperor Kaido. Not only did they bypass his Nigh-Invulnerability by literally dogpiling Kaido all at once, stabbing him together with their swords powered by their combined Haki but in fight proper, they turned the tables on Kaido’s dragon form cutting his fire in half and even deflecting it back down his throat with their abilities. They also take note of a large scar on Kaido's chest and focus as much on this scar as possible, knowing he's weaker and more sensitive there. Unfortunately Kaido eventually decided to get serious when Scabbards cut him up enough.
- In the Wano Flash Back a Voluntary Shape Shifter old woman on Kaido’s side was savvy enough to exploit Long-Dead Badass Oden’s Papa Wolf tendencies as when Kaido was getting pushed by Oden in their duel, the hag turned into Oden’s son Momonosuke and pretended to be a hostage which caused Oden to get distracted and swiftly struck down by Kaido. However Kaido was actually disgusted with this unclean victory and after killing the old woman, he actually apologised to Oden during the latter’s execution.
- He does the same after a CP0 agent promptly injures Luffy, using this chance to almost kill him. But Kaido is so incensed at the attempt, he severely injures the said agent and mourns for Luffy's "supposed" death in his own way, and once Luffy returns after awakening his Devil Fruit, Kaido is genuinely overjoyed to see him alive and expresses disgust in winning that way.
- Shanks proves himself to also be fulling willing to play dirty. When his future vision has him realize Kid would destroy his fleet in a single attack, he abandons his plans to have a fair fight with him and jumps onto Kid's ship and immediately hits him with a Divine Departure, blowing up Damned Punk before it could fire while also taking out Kid and Killer at the same time. He then has Doffy and Broggy destroy Kid's ship after they give him their Poneglyphs.
